Observers of Northern Irish politics might be forgiven for thinking that it's deja vu all over again, but in fact the scale of the recent unrest has taken many by surprise, following as it does upon last summer's relatively peaceful marching season. What has made this July so turbulent?

This summer's parades follow the publication of the Saville report, which exonerated the victims of Bloody Sunday. The report was welcomed by victims' groups and nationalists, and was gracefully acknowledged by David Cameron, who formally apologised to the victims and their families. However, despite the report making headline news nationally, on the day of publication only two unionist representatives, Reg Empey and Gregory Campbell, commented on Saville's findings, and both spoke critically of the report, its cost, and the dangers of creating a "hierarchy of victims", without acknowledging the report's conclusions. Peter Robinson, the first minister, remains the sole unionist politician to publicly acknowledge Saville's findings.

Saville provided a unique opportunity for unionists to engage in reconciliation, but that opportunity was squandered and as result division between Catholics and Protestants has intensified. What is interesting about this, though, is not just that an opportunity for reconciliation was missed (a depressingly predictable pattern of events in Northern Ireland), but that it went unremarked by the wider media, whose uncritical adoption of the "two divided communities" paradigm meant that the political debate was allowed to continue along predictable sectarian lines, regardless of the new historical evidence that Saville put forward.

One of the unfortunate consequences of this longstanding failure to engage meaningfully in reconciliation has been the rise of dissident republicanism. But placing the responsibility for Monday's violence solely with dissident republicans (as Sinn Féin and others have done) masks the widespread nature of opposition to Orange marches within the wider Catholic community. The Orange Order is an explicitly sectarian organisation, dedicated to protecting Protestant ascendancy in Northern Ireland. This is generally ignored in debates about contentious marches in Northern Ireland, which tend to characterise the conflict as between two extremist factions.

Rather than actively challenging the sectarian basis of Orangeism, the establishment has instead normalised Orangeism and even sought to promote it as a source of tourism. This often requires that the media adopt a somewhat incoherent attitude to reporting parades. Monday's local BBC news, for example, which concentrated on the widespread violence surrounding contentious marches, was followed by a programme entitled The Twelfth, which documented the parades as a national carnival and effaced any reference to their controversy or the violence they provoked.

Monday's violence demonstrates the futility of seeking to forge a peaceful future in a deeply divided society without challenging the underlying basis of those divisions. It is madness to encourage Catholics and Protestants to maintain their own competing versions of what is in reality a shared history, or to use public funds to promote exclusive cultural activities such as Orange marches. Rather than tolerating intolerance, an approach that merely serves to legitimate and reify sectarian cultural identities, politicians and the media need to address the underlying causes of social division in Northern Ireland (segregated schooling, housing and cultural activities). If Monday's scenes are not to be repeated, we urgently need to make a start on that much-vaunted, but still-elusive, project of building a shared future.